(a) Field of the Invention
The present invention is aimed to improve the conventional plane-opened hydrodynamic testing device, one or more than one reverse pumping return units (201) are installed with a parallel or substantially parallel manner at the periphery of an active fluid pumping unit (101), so a part of the fluid discharged from the outlet port of the active fluid pumping unit (101) is enabled to be sucked and reversely pumped for being returned to an adjacent space defined at the fluid inlet port of the active fluid pumping unit (101), thereby structuring a semi-opened hydrodynamic testing device having reverse pumping return unit.
(b) Description of the Prior Art
A conventional hydrodynamic testing device includes a closed circulating hydrodynamic testing device or an opened hydrodynamic testing device for pumping airflow or liquid fluid, wherein the opened hydrodynamic testing device, e.g. an opened hydrodynamic testing device adopting airflow as the fluid member (as known as a wind tunnel) is usually formed in a tubular structure and installed with a negative pressure or positive pressure fluid pump for pumping the fluid, the fluid is sucked from a fluid inlet port of the opened hydrodynamic testing device and discharged from a fluid outlet port of the opened hydrodynamic testing device and a testing platform is installed at the middle segment of the pipeline, thus two ends of the opened hydrodynamic testing device are required to respectively reserve a negative pressure space for sucking fluid and a positive pressure space for the fluid discharging stroke.